Preparation And Anti-swelling Evaluation Of Glycerol As Cold-resistant Clay Stabilizer

The majority of the oil layers with low Permeability always include clay mineral, and are also highly water-sensitivity. Clay stabilizer can effectively prevent clay swelling reservoir, Clay stabilizers have been widely studied over last decades; however, the usable method is still base preparation stabilizer, by truck to the job site. In the northern cold area, such as Daqing oilfield and Changqing oilfield, the disadvantage of this operation method is that the clay stabilizer is easy to freeze or precipitated solid at low temperature, which caused the inaccurate parameters of the clay stabilizer. The transport and storage of the clay stabilizer is another problem, cannot be used for directly operation. Therefore, the study of the antifreeze stabilizer at low temperature is necessary, which providing strong technical support for the development of the cold region soilfield operation techniques.This paper aiming to improving the anti-swelling and durability clay stabilizer, we select triethylamine and epichlorohydrin to synthesize a low molecular weight Gemini Quaternary clay stabilizer. Glycerol as an anti-freeze monomer, by adding glycerol to reduce the freezing point of the stabilizer, And compound with inorganic salt KCl improvehe anti-swelling rate. Then, we discuss the reaction temperature, reaction time, the molar ratio of reactants, et al, and obtain the optimum synthesis scheme. Determine the purity of the synthesized product through Elemental analysis, the melting point analysis and active content analysis; By anti-swelling experiments, cuttings recovery experiments, core dissolution experiments show stabilizer has good adsorption stabilizing effect.On the basis of the new cold clay stabilizer synthesis and evaluation of experiments, we achieve the following five conclusions:1. Gemini quaternary ammonium salt stabilizer can synthesize by epichlorohydrin and triethylamine. Based on the reaction temperature, reaction time, the molar ratio of reactant sand other aspects, the synthesis conditions are optimized. Dual quaternary product purity is 94.6% through reverse methylene blue titration. The critical micelle concentration is 4.8 mmol/L by measured the conductivity.2. By lab anti-swelling experiments, Anti-swelling property of synthetic quaternary clay stabilizer is analyzed, anti-swelling property, the recovery rate of cuttings and Core dissolution rate are also tested. The results showed good effects on the stability of clay. Besides, the optimal injection concentration of the stabilizers is determined.3. The compound of Gemini quaternary ammonium salt stabilizers and antifreeze glycerol monomer with several low-temperature experiments to determine the lowest concentration of glycerol and the anti-swelling rate was 81.2% under-20℃ without the precipitation of crystals.4. Mix the cold-type stabilizer and inorganic salts KCl, NH4CI to improve the anti-swelling rate stabilizer through anti-swelling optimization tests. The experiments show that after mixed KCl solution, anti-swelling rate is significantly higher than that of NH4Cl, reaching to 83.6%.5.The performance of corrosion the cold Gemini quaternary ammonium salt after compound was studied systemically. It was found that there was certain corrosion fo r A3 carbon steel. There was an effective protection for the tanks used for transport a nd storage.